Illuminating-body



A G. BERGMAN.

ILLUMINATING BODY.

APPLICATION FILED JULY 12. 1919.

1,38 1 ,445 Patented June 14, 1921.

INVENTOR WITNESS M W J m By Affofueys,

AXEL G. BERG-MAN, OF NEW YORK, N. Y.

, ASSIGNOR TO ORDINANCE ENGINEERING CORPORATION, OF NEW YORK, N. Y., ACORPORATION OF NEW YORK.

ILLUMINATING-BODY.

Application filed July 12,

To all who-m it may concern:

Be it known that I, Arm. G. Bn1ioMAN, a subject of the King of Sweden,residing 1n borough of Manhattan, city, county, and State of New York,have invented certain new and useful Improvements inIlluminating-Bodies, of which the following is a specification.

".lhe present invention provides an 1m proved gun projectile, of thestar or illuminating type, and improved elements of said projectile;particularly the illuminating body, and an igniting body for saidilluminating body, of especial utility in the case of projectilescontaining illuminating bodies of a construction and composition whichrender them of difficult ignition. The

present type of shell carries an illuminating charge which is usually inthe form of a mass of brilliantly burning material, and the compositionof which usually includes magnesium in some form. The illuminating bodywhich I prefer to use is made under heavy compression, from two tonsupward to the square inch, this compression having for its purpose toenable the illuminating body to vithstand the shock of being fired froma gun, to insure the most efliciency as regards the duration, intensity'and regularity of burning, and to render the illumir nating compositionless susceptible to impregnation by moisture.

According to certain of my prior inventions, I am enabled to provide aprojectile which is capable of use in high powered or rifled guns, sothat illumination may be eiiected considerable distances away from thegun, and some form of timing mecha uism is adopted, by which theilluminant will function at various points in the tra-' jectory of theshell, means being provided for checking the velocity of the illuminantat the time when it is desired that it shall function, and means beingalso provided for sustaining the illuminant in the air after ignition,and the projectile of the present invention preferably includesappropriate features of my said 'priorinventions.

In this type of projectile, especially, the muzzle velocity is usuallyvery high, ranging from 2,800 to 3,200 feet per second. While thisvelocity falls during the travel of the pro'ectile, it is found that inmost cases when t e illuminant is ignited, the latter,

1919. Serial No. 310,464.

still maintains a very rapid rate of travel, which is maintained for ashort time after the functioning of the igniting means until theilluminating body has been checked. Shells or projectiles of this typeare shown for instance in Patents os. 1,305,186, 1,305,187, and1,305,188, granted to me on ll'lay 27, 1919.

v In order to assist in the ignition of the illuminant composition, ithas been proposed to include in the end of the illuminating shell orstar a plug or pellet which is composed of quick burning powder, andwhich is exposed at one end to the flame of the igniting charge. Suchplugs have been made in cylindrical form, but have been foundunsatisfactory for the purpose, due probably to the fact that theexcessive draft caused by the rapid movement of the illuminant throughthe air draws or sucks the roducts of combustion of the igniting pel etrearwardl through the opening, so that insuflicient mat is developedagainst the contiguous walls of the illuminant to properly ignite it.

According to the present invention, the illuminating body is providedwith an embedded or included ignition body or pellet, which ignitionbody or pellet is preferably overhung by portions of the illuminatingbody, and is further preferably characterized by the fact that itsinterior cross-section is greater than its cross-section at the pointwhere it passes out to the outer wall of the star. Or in other words,the construction is such that the exit opening for the gases of thepellet'is restricted in area, so that such gases are maintained incontact with the contiguous wall of the star a sufficient length oftime' to insure ignition of the latter.

In the drawing, wherein I have shown one Form of the invention,-

Figure 1 is an elevation, partly in longitudinal section, of anilluminating body or star of cylindrical form, containing my improvedignitingpellet.

Fig. 2 is a plan view of the pellet itself.

Referring to the drawing, let A indicate the star which is formed of asuitable composition and which I prefer to construct according to themethod hereinafter described. Embedded in th rear or igniting end of theilluminant is the pellet or body B, the end Specification of LettersPatent. Patented J 111219 142, 1921. i

during the molding of which C extends to the rear end D of the star, oris otherwise exposed to an igniting flame.

According to the present invention the pellet or body B is preferably ofsuch shape that its interior'cross-section is greater than its exteriorcross-section where it emerges from the body of the composition. In theparticular construction illustrated the pellet is shown as being ofsubstantially frustoconical shape with a cylindrical base E.

In constructing the pellet, I prefer to use meal powder or fusepowderand to compress this powder to a very high pressure. I

' have found that admirable results are obtained if the pressureapproximates fifteen tons per square inch. The pellet may have anysuitable composition, however, but care should be taken that itscomposition is such that it will not explode. The purpose and effect ofsubjecting the pellet or igniting body to this great pressure is toreduce the time of burning of the powder or other material of which itis composed, so that the combustion is changed from an ordinary flash toa distinct interval of time, approximating two to threeseconds, thusproviding for a sustained combustion of the igniting body against thecontiguous walls of the illuminating body.

One practical means of introducing the pellet into the star is to moldit in during the molding of the star, the entire structure according tothe present invention. being preferably placed under about five tonspressure during the moldingoperation. For this purpose the particularconstruction of igniting pellet illustrated is of importance since ithas noweak points which might be disrupted during the heavy pressingoperation. It also has no thin flanges or portions which might be brokenoff either before or operation.

It is desirable that the end C of the pellet where it emerges from thestar shall be clean and bright, in order that it may certainly becomelgnited, and for this purpose I prefer to drill a small hole G which maybe of conical shape in the end of the pellet before the star is loaded.in the shell. I have also found it'desirable to face the end of the starwith a very light covering of blasting powder, which is indicated by theletter H, which, however, is best applied beforethe drilling operationjust described.

In loading the shell or projectile it will .be understood that theigniting charge is placed next to'or communicating with the layer ofplasting powder or the end of the pellet.

Upon the functioning of .the time fuse the igniting charge of the shellis-fired, and the pellet or igniting body B is-thereby ignited.

he latter burns .but does not flash :and generates .a high temperature,and the gases of combustion seek to rush out of the exlength of time toinsure the certain ignition of the star. Moreover. the igniting bodypreferably extends for a considerable depth into the illuminatingmaterial, thus assuring that the walls of the illuminating body will bewiped by the flames from said igniting body in passin outward. As hereshown, the igniting body extends a distance nearly twice its diameterinto the illuminating body. I

The pellet may be of various shapes other than that shown withoutdeparting from the invention. I have described this feature of theinvention with referenceto the shape of the pellet because of the factthat inpractice the pellet is usually constructed first and the walls ofthe star which surround it take their: shape from that of the pellet. Itwill be understood, however, that this feature of the invention may beregarded as comprising the formation of a star or similar body with arecess having a restricted orifice, in which recess an ignitingcomposition is placed. Preferably this orifice is formed in thecomposition of the star itself. For the best results, the restrictionmust be effected by the closing in of the composition to be ignited, sothat there will be an angular, rather than a substantially parallel,contact between the flame and the composition to be ignited.

This feature of the invention is applicable to other devices than thatindicated, and may be employed under any circumstances which demand apractically certain ignition of a more ditficultly ignitiblc body undersevere conditions. k

In constructing the illuminant or star, I preferably use barium nitrateand potassium nitrate, magnesium powder, aluminum powder. These aremixed warm with paraffin and the mass is then compressed under highpressure, preferably about five tons per inch. I'have found in practicethat. it is very important in the manufacture of such stars that thebarium, aluminum and magnesium be in a state which is thoroughly dry. Bythis I do not mean what is ordinarily regarded as dry in the sense ofbeing free from perceptible moisture, since I have found that theunexplained failure of manyprevious illuminants to ignite has been dueto a slight degree of moisture, such as would be the result of handlingor .mixing the several chemicals in a room; where there was a percentageof humidity of perhaps forty-five or fifty. degrees or over. Suchchemicals have heretofore been believed to be substantially nonandabsorbent, and the humidity of the mixing room has not heretofore beenthought to have any effect upon the igniting or burning qualities of theilluminant.

According to my invention I mix the several chemicals employed, or othersuitable chemicals, under conditions where the humidity does not exceedforty-five percent. and preferably where it is less than thirtyfive percent. As a matter of practice before mixing I thoroughly dry theingredients so as to make certain that they have no excess moisture.Whiletheingredients are in this dry state, they are mixed with paraffin,which while commonly used as a binder has the additional effect ofpreventing the ingredients from absorbing moisture, if afterward broughtinto contact with moist air. The use of paraflin in the case of what maybe described as n1oist ingredients has had precisely the contraryefi'ect in the past, since it prevented any possible evaporation of suchmoisture.

What I claim is 1. A projectile adapted to be discharged from a gun, andhaving therein a star mass or body, and means for igniting said starmass or body while in flight, said means comprising an igniting bodyembedded in said star mass or body, and having a face adapted to beexposed to an igniting flame, and means for restricting the flow ofgases out of the cavity produced by the progressive burning of saidigniting body,

whereby the rarefication behind said mass produced by the rapid flightthereof is prevented from affecting the combustion of said igniting bodyto an extent that will interfere with its action in igniting said starmass.

2. A projectile adapted to be discharged from a gun, and having thereina star mass or body, and means for igniting said star mass or body whilein flight, said means comprising an igniting body embedded in said starmass or body, and having a face adapted to be exposed to an ignitingflame, said star mass having a portion overhanging said igniting body,whereby the flame from said igniting body is caused to Wipe theoverhanging portion of said star mass, and whereby the rareficationbehind said mass, produced by the rapid flight thereof, is preventedfrom affecting the combustion of said igniting body to an extent thatwill interfere with its action in igniting said star mass.

A projectile adapted to be discharged from a gun, and having therein astar mass or body, and means for igniting said star mass or body whilein flight, said means comprising an igniting body embedded in said starmass or body, and having a face adapted to be exposed to an ignitingflame, said igniting body being reduced, at its exposed end, and saidstar mass having a portion overhanging said reduced portion, whereby theflame from said igniting body is caused to wipe the overhanging portionof said star mass, and whereby the rareflca- A projectile adapted to bedischarged from a gun, and having therein a star mass or body, and meansfor ignitingsaid star mass or body while in flight, said meanscomprising an igniting body embedded in said star mass or body, andhaving a face adapted to be exposed to an igniting flame, said ignitingbody being generally conical in shape, and having its smaller endoutermost, and said star mass having a portion of corresponding shapeoverhanging the said igniting body in a manner to restrict the flow ofgases out of the cavity produced by the progressive burning of saidigniting body, whereby the flame from said igniting body is caused towipe the overhanging portion of said star mass, and whereby therarefication behind said mass, produced by the rapid flight thereof, isprevented from affecting the combustion of said igniting body to anextent that will interfere with its action in igniting said star mass.

5. A projectile adapted to be discharged from a gun, and having thereina star mass or body, and means for igniting said star mass or body whilein flight, said means comprising an igniting body embedded in said starmass or body, and having a face adapted to be exposed to an ignitingflame, and means for restricting the flow of gases out of the cavityproduced by the progressive burning of said igniting body, whereby therarefication behind said mass, produced by the rapid flight thereof, isprevented from affecting the combustion of said igniting body to anextent that will interfere with its action in igniting said'ster mass.said igniting body having a relatively large area of contact with thestar mass along an axis running inwardly of said igniting body.

6. from a gun, and havingtherein a star mass or body, and means forigniting said star mass or body while in flight, said means A projectileadapted to be discharged comprising an igniting body embedded in saidstar mass or body, and having a face adapted to be exposed to anigniting flame, and means for restricting the flow of gases out of thecavity produced by the progressive burning of said "igniting body,whereby the rarefication behind said mass, produced by the rapid flightthereof, is prevented from affecting the combustion of said ignite ingbody to an extent that will interfere said star mass or body,

' the rareiication behind said mass,

with its action inigniting. said, star mass,

said igniting body having a length in the star mass along an axisinwardly thereof approximating or exceeding its breadth.

7. A projectile adapted to bedischarged from a gun, and having theiein astar mass or body, and. means for igniting said star inass or body whileinflight, said means comprising an igniting body embedded in and havinga face adapted to be exposed to an igniting flame, and means forrestricting the flow of gases out of the cavity produced by theprogressive burning of said igniting body, whereby produced flightthereof, is prevented by the rapid the combustion of said ignitfromaffecting ing bodyto an. extent that 'will interfere with its action inigniting said star mass, said igniting body being formed under pressuresufliciently high to reduce its combustion from a flash to an enduringflame.

8. A projectile adapted to be'discharged from a gun, and having'thereina star mass or body, and means for igniting said star mass or body whilein flight, said means comprising an igniting body embedded in said starmass or body, and having a face adapted to be, exposed to an ignitingflame, and means for restricting the flow of gases out of the cavityproduced by the progres sive burning or said igniting body, whereby therarefication behind said mass, produced by the rapid flight thereof,

ing body to an extent that will interfere with its action in ignitingsaid star mass, said igniting body being formed under pressuresufliciently high to reduce its combustion from a flash to anenduringflame, 15 tons per square inch being a representative pres.-sure in the case of gun powder.

9. A projectile adapted to be discharged from a gun, and having thereina star mass or body, and means for igniting said star mass or body whilein flight, said means comprising an igniting body embedded in said starmass or body, and having a face adapted to be exposed to an ignitingflame, and means for restricting the flow of gases out of'the cavityproduced by the progressive burning of said igniting body, whereby therarefication behind said mass, produced by the rapid flight thereof, isprevented from affecting the combustion of said igniting body to anextent that will interfere menses ofa rapid burningmaterial,

is prevented. from affecting the combustion of said ignitwith its actionin igniting said star mass, said star mass or bo y being-compressed soas to materially-reduce the power of absorption of moisture bysaidmass.

10. An igniting-body or pellet, composed and compressed under arepresentative pressure of 15 tons per square inch, whereby to prolongthe time of burning thereof from a flash-to the order of a second, saidbody having generally conical shape.

11. A star orilluminating mass or body, adapted to be projected from agun as apart of a projectile or shell, adapted to be ignited in rapidflight, ing body embedded body, having a face adapted to be exposed toan igniting-flame, and means for restricting the flow of gases-out ofthe'cavity produced by the progressive burning of said igniting-body,whereby the rarefication behind said mass, produced bythe rapid flightthereof, is prevented from affecting the combustion of said ignitingbodyin a manner that will interfere with its actionin igniting said starmass.

12.. A staror illuminatingmassor body, adapted to be projected from agun as a part of a projectile orshell, and adapted to be ignited inrapid flight, comprising an igniting body embedded in said star mass orbody, and having a face adaptedto be exposed to an igniting flame, saidstar mass having a portion overhangingsaid igniting body. v

13. A- star or illuminating mass or body, adapted to be projected from-agun as a part of a projectile or shell, and adapted to be ignited inrapid flight,,comprising ,an ignitsigned my name.

AXEL G. BERGMAN.

comprising an ignitin said star mass or ing b dyembedded in said starmasslor

